A recurrent issue in education is which spelling words should be taught and how they should be taught. A brief review of several articles that deal with the employment of spelling programs that have incorporated the 100 most frequently used words in their curriculum shows many similarities in philosophies and teaching methods. The concern about the 100 most frequently used words is not new: the earliest article reviewed was written in 1950. Why the persistence of this approach? Research shows that about 100 words make up half of all the words used in writing. If the student is accountable for these particular words, he/she can learn to recognize them instantly in order to achieve fluency in reading, writing, and spelling. The educator must choose the most effective method to implement the learning of the 100 words. Rebecca Sitton has developed groups of 3 types of spelling words: core words (lists of 10 words, divided by grade level); individual words (words each student selects for him- or herself); and priority words (former core words that students have mastered). Steve Graham and Karen Harris suggest a process known as preview, practice, and review. This method provides students with an efficient, systematic technique to study unknown spelling words. Many teachers still agree with the 6-step method developed by Ernest Horn in 1919, which asks students to memorize the word with their eyes closed and then write it down. (Contains the list of the 100 most frequently used words.) (TB)